Razi Journal of Medical Sciences

The enterococci are gram positive microorganisms. Currently they are considered as one of the most important causes of mortality in hospitalized patients. Enterococci are the 4th cause of nosocomial infections.

The importance of enterococci is due to the ability of these bacteria in developing resistance to a wide range of antibiotics. The other contributory factor is the potency of transmitting resistance to other microorganisms and their role as a reservoir for spreading resistance.

In this study, gastrointestinal colonization with vancomycin - resistant enterococci in hospitalized patients has been investigated. Stools or rectal swabs have been collected from 300 hospitalized patients and 100 controls. Enterococci were isolated in 290 of hospitalized patients and all of controls. The isolated enterococci were tested by "disk diffusion" for resistance to vancomycin and penicillin. All controls were sensitive to vancomycin, whereas in hospitalized patients 2 cases were considered as resistant and 22 cases seemed suspicious. By using serial dilution, sensitivity test was performed to determine minimal inhibitory concentration (MIC) for confirming resistance. 4 of 22 suspicious cases and 2 confirmed resistant cases had an MIG higher than 64 mg/L, and thus were considered resistant. In this study, the results reveal a resistance rate of 2.07% in hospitalized patients which is compatible with European studies.